Exhaust muffler



April 9, 1957 J. REINDL 2,788,078

EXHAUST MUFFLER Filed Dec. 2, 1954 INVENTOR JOSEPH RE/NDL ATTORNEY han f United States Patent O EXHAUST MUFFLER Joseph Reindl, Topanga, Calif. Application December 2, 1954, Serial No. 472,686 6 Claims. (Cl. 181-58) This invention relates generally to silencers and relates more particularly to devices of this character for muiing the exhausts of internal combustion engines.

While the invention has particular utility in the muil'ling of the exhaust gases in internal combustion engines and is shown and described in such connection, it is to be understood that its utility is not confined thereto.

It is an object of the invention to provide a muffler that is highly elfective in silencing the pulsating gaseous currents `of the exhaust of internal combustion engines.

It is another object of the invention to provide a device of this character which will have a cushioning effect upon the gases passing therethrough.

It is a further object of the invention to provide a device of this character having a minimum of back pressure.

A still further object of the invention is to provide a device of this character which will provide for expansion and cooling of the exhaust gases passing therethrough.

It is another object of the invention to provide a device of this character in which the exhaust gases passing therethrough are given a gyratory motion so that there is a vortex action of the gases.

Still another object of the invention is to provide a device of this character which will be effective in arresting expansion from the engine exhaust.

It is a further object of `the invention to provide a device of this character that is substantially self cleaning so that carbon deposits are reduced to a minimum.

A still further object of the invention is to provide a device of this character that is of relatively small size.

Another object -of the invention is to provide a device of this character that is compact and sturdy in construction.

Still another object of the invention is to provide a device of this character that is simple in construction and which may be readily assembled and produced at relatively small cost.

The characteristics and advantages of the invention are further sufficiently referred to in connection with the following detailed description of the accompanying drawings which are for illustrative purposes only and represent certain embodiments. After considering the disclosed examples, skilled persons will understand that many variations may be made Without departing from the principles disclosed, and the employment of any structures, arrangements or modes of operation that are properly within the scope of the appended claims are contemplated.

Referring to the drawings:

Fig. 1 is a longitudinal section through a mutller or silencing device embodying the present invention;

Fig. 2 is a section taken on line 2*2 of Fig. 1;

Fig. 3 is a fragmentary longitudinal section of an alternative arrangement; and

Fig. 4 is a section taken on line 4-4 of Fig. 3.

Referring more particularly to the drawings, the device comprises a tubular body 10 which is shown as being cylindrical but which may be of any suitable crosssectional shape. The ends of the cylinder 10 are closed by plates 11, each of which is provided with an axially extending flange 12 received within the end portions of the cylinder 10 and secured therein by any suitable means such as brazing, spot welding or the like. The plate at the inlet end of the device is provided with an inlet pipe 13 which communicates with the interior of the body 10 and which is adapted to be connected to the discharge end of the exhaust pipe of an inlet combustion engine not shown. The plate 11 at the opposite or discharge end of the device is also provided with a pipe, indicated at 14, which communicates with the interior of the body 10 and which is adapted to be connected to a tail pipe, not shown, or any other suitable conduit for carrying away the gases from the body 10. The pipes 13 and 14 are shown as being coaxial with each other and with the body 10. However, it is to be understood that either or both of said pipes may be eccentrically mounted relative to the axis of the body 10.

Within the body 10, in longitudinally spaced relationship to each other, there are a plurality of frusto-conical members, indicated generally at 15 and similarly arranged. In view of the fact that the frusto-conical members 15 have the same construction, it will be necessary to describe only one of said members.

Each member 15 comprises an inner frusto-conical part 16 and an outer truste-conical part 17, both said parts 16 and 17 being formed of sheet metal. Between the parts 16 and 17 is a layer of insulating material 18 which is shown as being asbestos. Within the member 15 is a tube 20 which has one end disposed within the smaller opening 21 of the member 15. The tube 20 is shown as not projected outwardly beyond the smaller end of frusto-conical member 15, but it is to be understood that it may project therefrom, said tube being secured to the truste-conical member 15 by any suitable means such as brazing, welding or the like. The inner end of the tube 20 is spaced inwardly of the large end of the member 15.

Within the tube 20 is a spiral vane 25 for causing swirling action of the gases passing through said tube 20. The Vane causes the speeding up of the movement of the gases in the tube 20 and thereby effects a reduction in back pressure.

Means for relieving surplus pressure is provided and comprises a plurality of openings 26 in the frusto-conical member 15 adjacent the pass thereof. The openings 26 are spaced around the member 15 and there are several rows which are spaced longitudinally with respect to said member.

There are also a plurality of annularly spaced openings 27 adjacent the small end of the member 15.

Having a plurality of the frusto-conical members 15 within the body 1t) said body is divided into a plurality of chambers, indicated at 28, 29, 30 and 31 respectively. While three of the members 15 are shown, it is to be understood that the number may be varied and varying the number of said member will correspondingly vary the number of chambers within the body 10.

Hot gases from the engine exhaust enter the chamber 28 where said gases expand and cool. Considerable portion of the gases entering chamber 28 pass through the tube 20 of the rst member 15. As pointed out hereinabove, the vane 25 within said tube causes the gases passing therethrough to swirl and the movement thereof to be speeded up. Surplus pressure is relieved through the openings 26 of this first member 15 and pass into the space 32 of chamber 29 wherein the pressure has been reduced due to the movement of the gases from the tube 20 through the central portion of the chamber 3 9 and twoard the tube 20 of the succeeding member The space 33 between the tube 20 of the iirst member and the adjacent interior wall thereof comprises a rebounce pocket and gases entering said pocket escape through the openings 27. It is to be noted that the lowered pressure within the pocket 32 aids in the movement of the gases from the rebounce 33 into the pocket 32 and hence toward the discharge end of the device. The openings 27 also provide means for drawing carbon and/or oil from the pocket 33 should such materials tend to collect therein.

By Varying the number of the openings 26, the number of the openings 27, the length of the tube and the length of the vane the sound of the exhaust may be varied. These variations may be made to meet various conditions in various types of installations.

It is also to be noted that while the vane 25 is shown as being of substantially the same length as the tube 20, the length of said vane may be varied with respect to said tube. For example, the vane may project from either or both ends of said tube or said vane may be short of either or both ends of said tube.

The central portion ofthe body of exhaust gases passing through the body 10, pass through the tubes 20 of successive members 15 and said gases are swirled by the vanes 25. Excessive pressure is relieved through the openings 26 of the respective members 15 and pass into the respective pockets 32 of the succeeding chambers 30 and 31 and the gases which enter the chamber 31 pass therefrom through the pipe 14 and if the latter is connected with a tail pipe or another conduit, said gases pass thereinto. ln the arrangement shown in Figs. 3 and 4, bales 35 are provided for supporting tubes 20 in which vanes 25 are disposed. The baies 35 are perforated at 36 to relieve successive pressure upstream of the peripheral portion of the body of gases passing through the device.

It is to be noted that in either embodiment of the invention, the adjacent ends of the tubes 20 are spaced apart and that there is no restriction at the downstream ends of said tubes.

I claim:

1. A muler for internal combustion engines comprising: a tubular body; plates closing the respective ends of said body, each plate having an axial opening therein; an outwardly extending pipe for each opening, one of said pipes being adapted to be connected to the outlet ot an exhaust pipe and the other being adapted to be connected to a tail pipe; a plurality of longitudinally spaced axially arranged truste-conical members within the body and secured at their bases to the interior side of said body, each of said members having the smaller end facing downstream in free suspension and comprising a pair-of frustoconical sheet metal parts and a layer of heat insulating material between said parts, there being a plurality of annularly spaced openings adjacent the smaller end of the member and a plurality of openings extending annularly about the member adjacent the larger end, each of said members having a tube extending from the smaller end inwardly toward the base and axially arranged with respect to said member, said tube terminating at the inner end in substantially the plane of the openings adjacent the larger end of said member; and a spiral vane extending longitudinally within the tube.

2. In a muler for internal combustion engines: a tubular body; plates closing the respective ends of said body, each plate having an axial opening therein; an outwardly extending pipe for each opening; a plurality of longitudinally spaced frusto-conical members within the body in axial alignment, each of said members having the large end thereof secured to the interior of said body and providing the sole support for said members so that the small ends are unattached with respect to said body, each of said members comprising a pair of frustoconical metal parts and a layer of heat insulating material between said parts, there being a row of annularly spaced openings adjacent the smaller end of the member and a plurality of rows of openings extending annularly about the member adjacent the larger end, a tube in each member extending from the smaller end inwardly toward the base and axially arranged with respect to said member, said tube terminating at the inner end between the planes of the rows of openings of the larger end of said member; and a spiral vane extending longitudinally Within the tube;

3. In a muler for internal combustion engines: a tubular body; plates closing the respective ends of said body, said body having an inlet and an outlet; a plurality of longitudinally spaced frusto-conical members within the body, secured at their bases to the interior side of said body and having the smaller ends thereof pointed toward said outlet, said members being supported entirely from their bases, each member comprising a pair of truste-conical metal parts and a layer of heat insulating material between said parts, there being a plurality of annularly spaced openings adjacent the smaller ends of the members and a plurality of openings extending annularly about said members adjacent the larger ends thereof; a tube for each member secured to and extending from the smaller end inwardly toward the base; and a spiral vane within the tube.

4. In a muier: a cylindrical body having an inlet at one end and an outlet at the opposite end', a frustoconical member within the body and secured at the base only to the interior side of said body, said member comprising a pair of frustoconical sheetmetal parts and a layer of heat insulating material between said parts, there being a plurality of annularly spaced openings adjacent the smaller end of the member and a relatively wide band of openings extending annularly about the member adjacent the larger end; a tube extending from the smaller end of said member toward the base and axially arranged with respect to said member, said tube terminating at the rear end in substantially the plane of the band of openings; and a spiral vane extending longitudinally within the tube.

5. ln a muier: a cylindrical body having an inlet at one end and an outlet at the opposite end; a frusto-conical member secured within the body only at the base end, said member having a plurality of openings spaced annularly adjacent the smaller end, and a plurality of openings adjacent the larger end; a tubular member secured within the smaller end; and means within said tubular member for effecting rotation of fluid flowing therethrough.

6. In a muiler: a cylindrical body having an inlet at one end and an outlet at the other end; a frusto-conical member secured only at the base to the interior of said body so that the small end is freely disposed in said body, said member having pressure relief openings therein; and means for electing rotative movement of uid flowing through the smaller end of said frusto-conical member.

References Cited inthe file of this patent UNITED STATES PATENTS 

